<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<!--<button onclick="f4">f4</button>-->
<script>
  function f1() {
    alert("f1")
  }
  function f2(name,age){
    alert(name+age)
  }
  function f3() {
    return "我是f3返回值"
  }
  function f4(x,y) {
    return x+y;
  }
  let resu = f4;
  console.log(resu(5,5))

  let f5 = function (name,age) {
    console.log(name+":"+age)
  }
</script>
</body>
</html>